Background: Subjective well-being is an essential ingredient in the quality of life concept. The Marburg questionnaire, a seven item scale for the assessment of the trait dimension of well-being, claims to possess good psychometric properties. This is investigated in two studies with chronic pain patients.
Methods: The first study utilizing a prospective, randomized, and controlled design, served to find out the effects of a pain management program. Included were 236 patients with a diagnosis of chronic low back pain (Toronto classification) or tension type headache (IHS classification). Study 2 employed a cross-sectional design and relied on the data of 186 patients mainly with pain in the back and the head who had filled in a pain questionnaire provided by the Schmerztherapeutisches Kolloquium, a German pain society.
Results: Across the studies, internal consistency of the scale with Cronbach's alpha=0.91 proofed to be very satisfactory; retest-reliability after an interval of eight weeks came up to r(tt)=0.81. The scale is one dimensional and demonstrates good replicability of the dimensional structure. The factor accounts for 65% of the variance of the test scores. Moreover, the scale is sensitive to change, and, therefore, can be used as an assessment tool in interventions that aim at an improvement of well-being. Interrelations with variables indicating chronicity support the concept of construct validity. This refers to the stage algorithm provided by the pain clinic in Mainz, to the affective dimension of the pain experience, to disability, depression, and inability to work.
Conclusion: The good psychometric quality of the questionnaire along with its brevity allows its application as part of a quality of life assessment.